Ranked by the provider's API Evangelist rating — the Kin Score is scored per provider, not per API, so every API of a provider shares its band. How the rating works →

Exemplar 38 Complete, well-documented, and agent-ready

HubSpot Calling Extensions APIThe calling extensions SDK enables apps to provide a custom calling option to HubSpot users directly from C...91.9 HubSpot Timeline Events APIThe timeline events API enables technology partners to send custom event data from external systems into Hu...91.9 HubSpot Video Conferencing APIThe video conferencing API enables you to integrate custom video conferencing solutions into HubSpot's meet...91.9 Canva Apps SDKBuild apps that extend Canva's editor with custom functionality, content, and integrations.87.3 Dynatrace Extensions API 2.0The Dynatrace Extensions API 2.0 provides endpoints for managing monitoring extensions including uploading,...85.6 Dynatrace Hub APIThe Dynatrace Hub API provides programmatic access to the Dynatrace Hub catalog content including apps, ext...85.6 Shopify Admin Extensions APIAdmin UI extensions allow developers to extend the Shopify admin with custom UI components. Extensions can ...83.8 Shopify Checkout UI Extensions APICheckout UI extensions let app developers build custom functionality that merchants can install at defined ...83.8 Shopify POS UI Extensions APIPOS UI extensions enable app developers to build custom functionality for Shopify Point of Sale. Extensions...83.8 Azure DevOps Extension Management APIAPI for managing extensions installed in an Azure DevOps organization. Enables programmatic listing, instal...81.9 Elastic Stack (ELK Stack) Extensions APIThe Extensions API from Elastic Stack (ELK Stack) — 2 operation(s) for extensions.80.8 Outreach Client Extensions APIClient extensibility surface for embedding a web application inside the Outreach client — shell, tab and ti...78.7 Optimizely Extensions APIManage reusable extensions that encapsulate experiment logic and visual changes.78.1 Confluence Dynamic modules APIThe Dynamic modules API from Confluence — 1 operation(s) for dynamic modules.77.7 Confluence V2 App Properties APIStore and retrieve app-specific properties in Confluence using the v2 API.77.7 Confluence V2 Custom Content APICreate and manage custom content types in Confluence using the v2 API.77.7 Automation Anywhere Package SDKThe Automation Anywhere Package SDK is a Java-based development toolkit that enables developers to build cu...76.7 Adobe Suite Extensions APIAn extension represents the installed instance of an extension package. An extension makes the features def...75.9 Microsoft Azure Extensions APIThe Extensions API from Microsoft Azure — 6 operation(s) for extensions.75.7 Adobe Experience Platform Reactor APIUse the Reactor API to programmatically manage resources and develop tag extensions in Adobe Experience Pla...75.5 AWS Lambda Extensions APIThe Lambda Extensions API enables you to create extensions that integrate with the Lambda execution environ...75.0 Trello Power-UpsTrello Power-Ups are a framework for extending and integrating with the Trello platform. Power-Ups allow de...74.1 GitHub Copilot Extensions APIPlatform for building Copilot Extensions that integrate third-party tools, services, and custom agents into...74.0 samva-dev Extensions APICode that receives mailbox events and acts through the mailbox API73.4 Amazon Systems Manager Systems Manager Extensions APIThe Systems Manager Extensions API from Amazon Systems Manager — 2 operation(s) for systems manager extensi...72.2 Microsoft Dynamics NAV Extensions APIManage installed extensions72.2 Qlik Sense Extensions APIThe extensions API from Qlik Sense — 4 operation(s) for extensions.72.2 Azure Arc Extensions APIThe extensions API from Azure Arc — 6 operation(s) for extensions.72.1 Docusign Connected Fields APIThe Docusign Connected Fields API enables developers to validate envelope field data programmatically. It a...71.5 Browser Use Extensions APIThe Extensions API from Browser Use — 2 operation(s) for extensions.71.1 Outlook Add-ins APIJavaScript API for building Outlook add-ins that extend Outlook functionality with custom features, using t...70.8 Adobe Launch Extensions APIManage extensions installed in event forwarding properties.70.5 Office Add-ins APIJavaScript API for building add-ins for Word, Excel, PowerPoint, and Outlook.70.1 Office Add-ins PlatformPlatform for building solutions that extend Office applications including Excel, Outlook, Word, PowerPoint,...70.1 Medusa Framework (Modules, Workflows, Routes)Server-side framework primitives for extending Medusa - custom API Routes, Modules with their own data mode...69.8 MATLAB MEX APIBuild MEX functions that enable calling C, C++, and Fortran code from MATLAB, with support for both the C++...68.8 Amazon Web Services Extensions APIThe Extensions API from Amazon Web Services — 2 operation(s) for extensions.68.5 Tealium iQ Profiles APIProvides programmatic access to iQ Tag Management configuration, allowing retrieval and modification of tag...66.5

Strong 23 Solid coverage with minor gaps

Azure Virtual Machine Extensions REST APIREST API for managing Virtual Machine Extensions, which provide post-deployment configuration and automatio...64.2 Bentley Systems Extensions APIExtensions resources for the iTwin Scenes API.63.3 Phone Com Extensions APIYour Phone.com account will have one or more extensions.63.0 Foxglove Technologies Extensions APIThe Extensions API from Foxglove Technologies — 3 operation(s) for extensions.62.8 Call2Me Extensions APIThe Extensions API from Call2Me — 17 operation(s) for extensions.62.5 Jane Extensions APIThe Extensions API from Jane — 2 operation(s) for extensions.61.8 Jane Extensions APICreate, read, update, delete, and list Jane Extensions, and browse the catalog of approved extensions avail...61.8 Commercetools Merchant Center Customizations APIThe commercetools Merchant Center Customizations API provides the programmatic interface for building custo...61.5 Kernel Extensions APICreate, list, retrieve, and delete browser extensions.60.9 SharePoint Framework (SPFx)The SharePoint Framework (SPFx) is a development model for building client-side web parts, extensions, and ...60.9 Swell Apps PlatformSwell Apps extend the platform with custom data models (added fields or new entities), events (triggering f...60.6 Webflow Designer Extension APIThe Webflow Designer Extension API allows developers to build extensions that run inside the Webflow Design...60.5 Excel JavaScript APIJavaScript API for building Excel add-ins and extensions.59.3 Knostic Extensions APIVS Code / IDE marketplace extensions with risk assessment59.0 AIMEAT Extensions APINode Extension System — V8 isolate sandbox for operator-installed plugins58.8 Chrome Extensions APIAPIs for building Chrome browser extensions.58.8 LambdaTest Extensions APIThe extensions API from LambdaTest — 2 operation(s) for extensions.58.8 RingCentral Extensions APIThe Extensions API from RingCentral — 5 operation(s) for extensions.58.7 RingCentral Provisioning APIThe RingCentral Provisioning API supports account, extension, user, phone-number, device, and role lifecycl...58.7 Dataiku Plugin APIAPI for developing custom plugins that extend Dataiku DSS with custom datasets, recipes, processors, and we...58.2 Looker Extension Framework APIThe Looker Extension Framework provides APIs and SDKs for building custom extensions that run inside the Lo...58.1 Browserbase Extensions APIThe Extensions API from Browserbase — 2 operation(s) for extensions.58.0 Safari Extensions APIAPI for building Safari Web Extensions that extend and customize the browsing experience.56.9

Developing 27 Usable, with meaningful gaps to close

SAP Lumira Discovery Extensions APIJavaScript API for creating custom visualizations and extensions in SAP Lumira.53.7 OpenShift Console APIAPI for managing OpenShift web console extensions including ConsoleCLIDownload, ConsoleExternalLogLink, Con...53.2 Adobe UXP (Unified Extensibility Platform)The Unified Extensibility Platform (UXP) is Adobe's modern cross-app plugin development framework replacing...53.0 PagerDuty Extensions APIExtensions are representations of Extension Schema objects that are attached to Services.52.1 Hyperbrowser Extensions APIUpload and list custom Chrome extensions that can be attached to browser sessions for advanced automation, ...51.9 Wazo Extensions APIThe extensions API from Wazo — 12 operation(s) for extensions.48.9 Twitch Extensions APIManage and query extension information48.2 QlikView JavaScript APIJavaScript API library for building websites containing QlikView content and for developing custom extensio...48.0 QlikView Plugin APICOM-based API for creating custom objects and extensions in QlikView.48.0 Dependency-Track Extensions APIEndpoints related to extensions47.2 Docupilot Extensions APIThe extensions API from Docupilot — 10 operation(s) for extensions.46.0 Zoho Cliq Extensions APIExtensions Module46.0 Flow Extension APIEnriches processes and documents including purchase orders, invoices, ASNs, order confirmations, and receip...45.7 SAP Ariba Custom Forms APIEnables creation and management of custom forms for extending procurement and sourcing processes with addit...45.7 Anchor Browser Extensions APIThe Extensions API from Anchor Browser — 2 operation(s) for extensions.45.3 Envoy API V3The Envoy API v3 is the current stable protobuf-based configuration and extension API for Envoy proxy. It d...43.9 Make Custom AppsThe Make Custom Apps platform enables developers to create their own applications for the Make automation p...43.4 Porter Mixins APIExtension interface for building and using mixins, which are the building blocks for authoring Porter bundl...42.3 Porter Plugins APIPlugin interface that allows extending Porter's core functionality, such as storing installation data, cred...42.3 Akeneo Extensions APIExtensions allow you to extend the Akeneo PIM user interface with custom components. They can be used to ad...41.6 Fly.io Extensions APIThe Fly.io Extensions API is a provider-facing HTTP interface that enables third-party services to integrat...41.5 Helm PluginsThe Helm Plugins API defines the interface for extending the Helm CLI with additional subcommands. Plugins ...41.0 Adobe Illustrator CEP Extensions APIThe Adobe Illustrator Common Extensibility Platform (CEP) allows developers to build panels and extensions ...40.9 Adobe Illustrator Plugin SDKThe Adobe Illustrator Plugin SDK enables developers to build native C++ plug-ins for Illustrator on Windows...40.9 JupyterLab Extension APIJavaScript and TypeScript API used to build JupyterLab extensions and plugins. JupyterLab is composed of pl...40.7 TESSA Marketing & Technology Extensions APIThe Extensions API from TESSA Marketing & Technology — 6 operation(s) for extensions.40.3 Kittl SDK & App PlatformThe Kittl SDK is the bridge between a sandboxed app and the Kittl editor host. It exposes async namespaces ...39.8

Thin 22 Limited public surface area

Celery Signals APISignals API for hooking into Celery lifecycle events including task, worker, beat, and consumer signals to ...39.2 Freshworks App SDKThe Freshworks App SDK enables developers to build custom applications and extensions that run within the F...39.0 Lucid Extension APIBuild extensions that run inside Lucidchart, Lucidspark, and Lucidscale editors. Read and modify canvas con...37.9 Unity Platform APIThe Unity Cloud (Unity Platform) developer surface, documented publicly at docs.unitycloud.io as the Unity ...37.6 Tableau Extensions APIBuild dashboard extensions that enable users to interact with data from other applications directly in Tabl...37.3 Craft eXtension APIThe Craft eXtension API is an official TypeScript/JavaScript SDK (@craftdocs/craft-extension-api) for build...36.3 Jaeger Remote Storage APIThe Jaeger Remote Storage API is a gRPC-based interface that allows extending Jaeger with custom storage ba...36.3 Enterprise Architect Add-In FrameworkFramework for building custom add-ins that extend Enterprise Architect with new functionality. Add-ins can ...36.2 TYPO3 REST API Extension (t3api)The sourcebroker/t3api extension provides an easy-to-configure REST API layer for TYPO3 Extbase models. API...35.9 Obsidian Plugin APIIn-app TypeScript/JavaScript Plugin API for building Obsidian plugins. Plugins access the Vault, Workspace,...34.9 Visual Studio Extensibility APIThe Visual Studio Extensibility API enables developers to create extensions that customize and extend Visua...34.3 Visual Studio Live Share APIExtension-facing API (via the vsls npm module) that allows other VS Code and Visual Studio extensions to st...34.3 Visual Studio Marketplace APIThe Visual Studio Marketplace API provides access to the extension marketplace for Visual Studio, VS Code, ...34.3 VS Code Extension APIThe VS Code Extension API enables developers to build extensions for Visual Studio Code. It provides APIs f...34.3 VS Code Marketplace Extensions APIQuery, search, and retrieve VS Code extensions from the Marketplace34.0 Penpot Plugin APIPenpot's Plugin API allows developers to build and publish custom extensions that extend the Penpot design ...30.5 WasmEdge Plugin SystemWasmEdge's plugin system enables extending the runtime with custom host function packages. Plugins can be d...30.5 Windstream Holdings Extensions APIExtension management30.3 Freshdesk App SDKThe Freshdesk App SDK allows developers to build custom applications that extend the functionality of the F...29.7 JupyterLabNext-generation web-based interactive development environment for notebooks, code, and data, with a Jupyter...29.3 Blender Extensions PlatformThe Blender Extensions Platform (extensions.blender.org) provides a curated repository of addons, themes, a...27.9 SPX Graphics Extensions APIInvoke functions in custom SPX extensions27.9

Emerging 10 Early or largely undocumented

Raycast Extension API (SDK)The primary developer interface - the @raycast/api npm package. A strongly typed TypeScript/Node SDK (insta...24.5 Raycast StoreThe Raycast Store distributes community and partner extensions. Publishing is done via the `ray` CLI and a ...24.5 Manifold Creator Core Smart ContractsOpen-source Solidity smart contract framework for deploying ERC721 and ERC1155 creator-owned NFT contracts....23.9 Better Auth PluginsFirst-party plugin ecosystem covering two-factor authentication, passkeys, magic link, organizations and te...21.3 Nostr Implementation Possibilities (NIPs)NIPs are the standards documents that extend Nostr beyond the core protocol. They define event kinds (text ...21.2 QRadar GUI App Framework APIAPI for developing and managing QRadar apps and extensions.20.3 Higress Wasm Plugin APIThe Higress Wasm Plugin API provides a WebAssembly-based extension interface for developing and deploying c...20.2 OpenInfra Foundation Extensions APIThe Extensions API from OpenInfra Foundation — 1 operation(s) for extensions.19.8 Thymeleaf Extras and DialectsAdditional Thymeleaf dialect extensions including the Java 8 Time dialect for date/time formatting, the Spr...18.5 Varnish Modules (VMODs)VMODs are extensions written for Varnish Cache that extend VCL capabilities. Bundled modules include blob (...15.8

Minimal 1 Almost no public developer surface

Arc Chromium ExtensionsArc inherits the Chromium / Chrome Web Store extension model, so any Manifest V3 extension can be installed...10.9

Companies reaching this through an API (96)

These companies publish an API, specification or operation carrying “Extensions” but do not classify their business under it. Listed unranked and kept out of the count above, because one tagged operation is not a statement about what a company does.

Adobe Adobe Creative Cloud Adobe Illustrator Adobe Launch Adobe Suite AIMEAT Akeneo Amazon Systems Manager Amazon Web Services Anchor Browser Apple Safari Arc (The Browser Company) Ariba Automation Anywhere AWS Lambda Azure Arc Azure DevOps Azure Virtual Machines Bentley Systems Better Auth Blender Browser Use Browserbase Call2Me Canva Celery commercetools Confluence Dataiku Dependency-Track Docupilot Docusign Dynatrace Elastic Stack Envoy Fly Io Foxglove Technologies Freshdesk Freshworks Google Chrome Helm Higress HubSpot Hyperbrowser IBM QRadar Security Intelligence Platform Jaeger Jane Jupyter Kernel Knostic

Show all 96 companies ↓

Looker Lucidchart Make Manifold MATLAB Medusa Microsoft Azure Microsoft Dynamics NAV Microsoft Excel (Advanced) Microsoft Office Microsoft Office 365 Microsoft Outlook Microsoft SharePoint Nostr Obsidian OpenInfra Foundation Optimizely Outreach PagerDuty Penpot Phone Com Porter Qlik Sense QlikView Red Hat OpenShift RingCentral samva-dev SAP BI Tools Shopify Sparx Enterprise Architect SPX Graphics Swell Tableau Desktop Tealium TESSA Marketing & Technology TestMu AI Thymeleaf Trello Twitch TYPO3 Varnish Cache WasmEdge Wazo Webflow Windstream Holdings Zoho Cliq

Score breakdown

Frequency

57.8

log-scaled weighted occurrences

Breadth

0.2

spread across providers

Quality lift

37.5

mean composite of providers using it

Cohesion

10.8

strength of nearest seed neighbor

Where this tag comes from

Api tag119

Provider tag16

Openapi tag31

Openapi op tag181

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Extensions

Providers using this tag (16)

APIs with this tag (121)